tag:blogger.com,1999:blog-8712770457197348465.post304994559186250373..comments2016-12-09T17:29:28.493-08:00Comments on Javarevisited: 10 Examples of HotSpot JVM Options in JavaJavin Paulhttps://plus.google.com/114528699166048052030noreply@blogger.comBlogger21125tag:blogger.com,1999:blog-8712770457197348465.post-53987411252232711142014-11-06T17:21:46.525-08:002014-11-06T17:21:46.525-08:00&gt; _they_ are not guaranteed to be supported on ...&gt; _they_ are not guaranteed to be supported on all JVM implementations<br /><br />&gt; -_Xss_ set java thread stack size<br /><br />Typos.<br />Ikemhttp://www.blogger.com/profile/13192982197895876155noreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-35981833490290362082014-03-03T13:54:15.511-08:002014-03-03T13:54:15.511-08:00The option &quot;-XX:NewRatio=2&quot; is for New/...The option &quot;-XX:NewRatio=2&quot; is for New/Old gen in Heap size not for &quot;Perm Gen Size&quot;<br /> <br />techcookerhttp://www.blogger.com/profile/10027009257929451179noreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-82529559880600662172014-02-04T22:50:43.678-08:002014-02-04T22:50:43.678-08:00I am New to this subject and willing to know that ...I am New to this subject and willing to know that where to Implement these JVM commands and how ? will be glad if u can provide the Sample for this DanteVickhttp://www.blogger.com/profile/08155925933709910934noreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-91959630704987647332013-12-14T16:11:19.300-08:002013-12-14T16:11:19.300-08:00I was asked -server , -client VM option in a recen...I was asked -server , -client VM option in a recent interview. I have never used it but it seems it&#39;s used a lot in finance domain. It would be nice if you can include it.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-42449976298817247502013-11-12T19:42:23.659-08:002013-11-12T19:42:23.659-08:00HeapDumpPath , JVM dumps the heap only in case of ...HeapDumpPath , JVM dumps the heap only in case of outofmemoryerror for debugging purpose am I correct ? This dump is used for the debugging purpose to find out the memory leak which has caused the out of memory exception. adityahttp://www.blogger.com/profile/00457542226593197417noreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-33111307253998674062013-07-10T21:35:51.419-07:002013-07-10T21:35:51.419-07:00Hi guys, What is the JVM command to print loading ...Hi guys, What is the JVM command to print loading and unloading of class files into memory? Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-3717787814132195912013-06-11T12:51:48.484-07:002013-06-11T12:51:48.484-07:00Thanks Javin! I really had no idea about JVM param...Thanks Javin! I really had no idea about JVM parameters ever and I recently got a project requirement on Performance Tuning. Seriously, I wouldn&#39;t have ever known it was this easy if you wouldn&#39;t have written this article!! Thanks a ton! :DZimhttp://www.blogger.com/profile/18360820547787868784noreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-43089955995128718412013-03-20T07:31:51.279-07:002013-03-20T07:31:51.279-07:00Very good article....thanks!Very good article....thanks!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-27242271913132913782013-01-29T07:00:10.314-08:002013-01-29T07:00:10.314-08:00So what is the stable standard jvm option? So what is the stable standard jvm option? Roberto Guerrahttp://www.blogger.com/profile/00203320521568074957noreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-72116804731155918362013-01-07T07:08:38.690-08:002013-01-07T07:08:38.690-08:00Hi Anyul, that&#39;s is very unlikely of running o...Hi Anyul, that&#39;s is very unlikely of running out of Perm Gen, I would rather check for classloader leaks. You may wan to check this post on <a href="http://javarevisited.blogspot.com/2012/01/tomcat-javalangoutofmemoryerror-permgen.html" rel="nofollow">ClassLoader leak on Tomcat and causing PermgGen error</a>Javin @ CyclicBarrier Example Javahttp://javarevisited.blogspot.sg/2012/07/cyclicbarrier-example-java-5-concurrency-tutorial.htmlnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-11253633764649156042013-01-07T04:44:47.653-08:002013-01-07T04:44:47.653-08:00is it possible for a web app to generate java.lan...is it possible for a web app to generate java.lang.OutOfMemoryError:Perm Gen Space by having to many system.out.println() outputs? I checked a heap dump generated on this kind of errors and found too many char[] arrays on my memory instanced.Anyul Rivashttp://www.blogger.com/profile/13970052852527981843noreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-29256189951675250522012-06-12T21:23:49.898-07:002012-06-12T21:23:49.898-07:00most important JVM option for memory and performan...most important JVM option for memory and performance in 64 bit JVM is -XX:+UseCompressedOops, which reduces size of pointers used inside JVM to 32 bit in a 64 bit machine, enabling CPU to cache more data and improve performance. It also helps to reduce GC pauses significantly.Ryannoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-34629064496260477072012-06-07T23:54:37.353-07:002012-06-07T23:54:37.353-07:00JVM options for memory can also include Setting up...JVM options for memory can also include Setting up PermGen space. like -XX:PermSize for specifying size of PermGen and -XX:MaxPermSize for specifying maximum size of PermGen space. Also JVM options for tuning Young and Old Generatiosn like -Xmn , -XX:SurvivorRation and -XX:UseAdaptiveSizePolicy can be very useful. Anyway turning JVM for performance or memory is continuous task in Java developmentJohnnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-59031744911843690812012-01-04T04:49:21.270-08:002012-01-04T04:49:21.270-08:00Hi Anonymous, JVM options with -D are system prope...Hi Anonymous, JVM options with -D are system property and you can access them by using System.getProperty(&quot;user.timezone&quot;). you can pass any property value in format -Dproperty=value to JVM. -X and -XX are actual JVM options difference is that -XX are non statndard option and may not be supported on all JVM e.g. may supported in HotSpot JVM but may not be in IBM&#39;s JVM.Javin @ JDK vs JREhttp://javarevisited.blogspot.com/2011/12/jre-jvm-jdk-jit-in-java-programming.htmlnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-9673065184482307592012-01-04T03:06:26.187-08:002012-01-04T03:06:26.187-08:00There are some JVM options with -D also .What exac...There are some JVM options with -D also .What exactly is the differneces between -D vs -X vs -XXAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-48477652464479522742011-11-19T19:55:10.137-08:002011-11-19T19:55:10.137-08:00Nice JVM Parameters list, I have copied this list ...Nice JVM Parameters list, I have copied this list of JVM options and kept in my desk for quick reference. ThanksAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-20842836800855402732011-11-17T17:23:40.613-08:002011-11-17T17:23:40.613-08:00Thanks for your comments Sandeep. Indeed Memory ad...Thanks for your comments Sandeep. Indeed Memory adjustment in Eclipse is quite common because it ran out of Memory while working with large projects.Javin @ Enum in Javahttp://javarevisited.blogspot.com/2011/08/enum-in-java-example-tutorial.htmlnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-27215501705174118242011-11-17T17:22:26.394-08:002011-11-17T17:22:26.394-08:00@Anonymous, Thanks for &quot;-XX:+HeapDumpOnOutOfM...@Anonymous, Thanks for &quot;-XX:+HeapDumpOnOutOfMemoryError&quot; , this is indeed an useful JVM option. Heap dump can help while diagnosing <a href="http://javarevisited.blogspot.com/2011/09/javalangoutofmemoryerror-permgen-space.html" rel="nofollow">OutOfMemoryError in Java</a>.Javin @ Generics in Javahttp://javarevisited.blogspot.com/2011/09/generics-java-example-tutorial.htmlnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-39180118854248887972011-11-17T03:48:06.640-08:002011-11-17T03:48:06.640-08:00Very good points. Also all memory heap options are...Very good points. Also all memory heap options are applicable to eclipse which can be configured in eclipse.ini file.<br /><a href="http://extreme-java.com" rel="nofollow">Extreme Java</a>Sandeephttp://www.blogger.com/profile/14459583259453333684noreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-74734615902097901582011-11-15T07:03:39.723-08:002011-11-15T07:03:39.723-08:00Here is another very useful option I think every j...Here is another very useful option I think every java programmer needs to know of:<br />-XX:+HeapDumpOnOutOfMemoryError<br /><br />This will dump a hprof file on the moment<br />an outofmemory occurs. This hprof file <br />can than be debugged with eclipse memory<br />analyzer.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-44268334014955733732011-11-08T06:08:08.303-08:002011-11-08T06:08:08.303-08:00where are the logs located?? any specific folder?where are the logs located?? any specific folder?Anonymousnoreply@blogger.com